In the last few years, wireless sensor networks have gained worldwide attention from both the research communities and the actual users. It comprises of a large number of extremely small autonomous computing, communication, and sensing devices, with limited energy and computing capabilities which co-operates to accomplish a large sensing task. Wireless sensor network raise some problems like limited energy resources replacement task. Therefore, good functions of such networks depend on energies of nodes. In this paper, two analytical models which predict the QOS in terms of throughput, jitter and average end-to-end delay and energy consumption have been introduced.